With mobile, I bet contention and poor signal are more of an issue. 5G is a noticeable improvement over LTE, and I am not sure they can do much better.
FYI, the air link latency for LTE was given as 4-5 ms. FDD as it's the best here. The 5G improvement to 1ms would require features (URLLC) that nobody implemented and nobody will: too expensive for too niche markets.
The latency in a cellular network is mostly from the core network, not the radio link anymore. Event in 4G.
(telecom engineer, having worked on both 4G and 5G and recently out of the field)
In a professional context, nobody knows it all in details. There are specializations: core network and RAN, and inside RAN protocol stack vs PHY, and in PHY algos vs implementation, etc.
You can see all the cellular specs (they're public) from there: https://www.3gpp.org/specifications-technologies/specificati...
5G (or NR) is the series 38 at the bottom. Direct access: https://www.3gpp.org/ftp/Specs/archive/38_series
It's a lot ;) But a readable introduction is the 38.300 spec, and the latest edition for the first 5G release (R15, or "f") is this one: https://www.3gpp.org/ftp/Specs/archive/38_series/38.300/3830...
It's about as readable as it can get. The PHY part is pretty awful by comparison. If you have a PHY interest, you'll need to look for technical books as the specs are quite hermetic (but it's not my field either).
I have never seen this. Where do I have to get 5G service to see these latencies?
If you search "5g latency", Google's AI answer says 1 ms, followed by another quote lift from Thales Group™ saying 4G was 20 ms and 5G is 1ms.
Once you scroll past the automated attempts, you start getting real info.
Actual data is in the "SpeedTest Award Report" PDF, retrieved from https://www.speedtest.net/awards/united_states/ via https://www.speedtest.net/awards/reports/2024/2024_UnitedSta....
Spoiler: 23 ms median for fastest provider, T-mobile.
(at least, I don't recall being able to get that sort of info from iOS APIs, nor have I ever seen data that would have required being derived that way)
I can only speculate 5G was so saturated on the initial rollout so it led to congestion and now its stabilized. But latency isn't only affected by distance and hops - congestion matters.